1. Field of the Invention
The invention relates to a mobile communication system such as a microcell-type personal handy-phone system (PHS), or a macrocell-type mobile phone system.
2. Description of the Related Art
As is well known, a mobile communication system is provided with a plurality of base stations which individually form radio zones. A calling area of a mobile terminal device is usually formed by a set of a plurality of radio zones. Such a system of this kind is classified roughly into a microcell type and a macrocell type in response to the extent of the radio zone also referred to a cell.
One system may includes the base stations in several tens of thousands, to monitor and control each base station, each base station is accommodated into one base station control device with a certain amount of base stations put together, and the base stations are monitored in groups. For instance, a technique concerning a maintenance management function of the system including the base stations is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-124869.
In recent years, with the advance and wide use of the microcell type, the number of base stations has increased more and more. After starting the use of the next-generation PHS system of which the future spread is expected, it is prescribed of further increase in the number of base stations in future. As the number increases, the number of base station control devices has also increased, in the present situation interfaces for control and management are not uniformized. In such a situation, the system gets behind to find failures; it takes a long time to identify examination, and then, there is a possibility of an occurrence of a trouble in operation of the system.
To begin with, it is necessary to manage and control the base station control device itself by means of any device, and there is the danger of breakdown of the system because of a complicated hierarchical structure of control with enlargement of the system. Like an existing technique, managing and controlling the base stations and the base station control devices by means of individual devices may be a big obstacle to development of the mobile communication system in future.